Information processing by the human brain was monitored and quantified by averaged evoked response techniques. The electrographic activity was recorded from left and right brain regions during perception in normal subjects, and was compared with that of patients with neuropsychiatric disorders (Alzheimer's). Suspect electrographic disturbances in brain-behavior relations in phsychiatric patients were also evaluated, relating left brain dysfunction to ideational disorders, and right brain activity to maladaptive emotional reactions.